Microlapping machine



H. s. INDGE Q 2,201,955

MICROLAPPING MACHINE May 21, 1940.

Filed Feb. 3, 1939 5 Sheets-Sheet 1 HERBERT 5. INDGE May 21', 1940.

H. S. INDGE MICROLAPPING MACHINE Filed Feb. 3, 1939 5 Sheets-Sheet 2 L on.

May 21, 1940. H. s. INDGE MICROLAPPING MACHINE 5 Sheets-Sheet 3 Jrwcmm HEHBEHTSJNDGE' Filed Feb. 3, 1939 May 21, 1940. H. s. moss MICROLAPPING MACHINE Filed Feb. 5, 1939 5 Sheets-Sheet 4 May 21, 1940. H. s. INDGE MICROLAPPING MACHINE Filed Feb 3, 19:59

5 Sheets-Sheet 5 3mm HERBERT 5. INDGE.

Patented May 21, 1940 Herbert S. lindge, i estboro, assignor to Norton Company, Worcester, Mesa, 2. corporation oi? ll'lassachusetts Application February 3, 133%, Serial No. 254,447

9 (Claims.

The invention relates to grinding machines, and more particularly to an abrading or lapping machine for surfacing internal cylindrical surfaces.

One object of the invention is to provide a simple and thoroughly practical internal lapping or abradingmachine of the planetary type for producing a microlapped internal cylindrical sur face. A further object of the invention is to provide an internal planetary lapping machine in which the grinding wheel is rotated, revolved and reciprocated axially. A further object of the invention is to provide an internal planetary type lapping machine in which the grinding Wheel may be rotated at a variable speed, the grinding wheel may be revolved at a variable speed, and the grinding Wheel maybe rcciprocated axially at a variable speed and through a variable stroke. Other objects will be in part obvious or in part pointed out hereinafter.

The invention accordingly consists in the featuresof construction, combinations of elements, and arrangements of parts, as will be exemplified in the structure to be hereinafter described, and the scope of the application of which will be indicated in the following claims.

In the accompanying drawings, in which is shown one of various possible embodiments of the mechanical features of this invention,

Fig. 1 is a front elevation of the improved machine;

Fig. 2 is a fragmentary front elevation, on an enlarged scale, of the lapping Wheel head, showing the wheel spindle and its mounting in cross section;

3 is a fragmentary left-hand end elevation, on an enlarged scale, having the wheel spindle reciprocating mechanism removed;

Fig. 4 is a fragmentary left-hand elevation, on an enlarged scale, showing the Wheel spindle reciprocating mechanism;

Fig. 5 is a fragmentary perspective View of the wheel spindle r ciprocating mechanism;

Fig. 6 dice; smatic illustration of the lapping machine driving mechanism;

Fig. 7 is an enlarged sectional view of the Wheel spin-rile driving pulleys;

Fig. 8 is a cross sectional view of the pulley assembly for revolving the lapping Wheel; and

Fig. 9 is a. fragmentary sectional View, on an enlarged scale, through the rear. spindle hearing.

A microlapping machine has been illustrated in the drawings comprising a base it which sup.- ports a longitudinally reciprocable Work supporting table II. The table ii is mounted to is provided with an adjustable platen i2 Which is substantially c a: hat shown in the expired prior patto J. N. Heald No. 1,285,159 dated November main drive motor l5 mounted on the rear the machine base is connected by a driving belt i. i -1 a pulley mounted on the end of a romain drive shaft it. A pulley if! on the it connected by means of a driving'belt 1 shaft 22 and is connected by a with a pulley 25 which is mounted and of a drive shaft 25 of a change-speed r mechanism 2? which is contained within a busing on the front of the machine base. A ivotaily mou. control lever 29 is connected to driving key (not shown) within the speed mechanism 2? so that any one of three speeds may be obtained. The speed change mechanism 2i serves to rotate a shaft 3!) i l nnected to operate a Work table driving reve. ing mechanism contained within a hour on the front of the machine base.

The reversing mechanism employed for driving and reversing the table II may be the standard l-known load and fire clutch mechanism such s is old and well known in the art. The shaft 30 provided with a reversing clutch 32 which is ly keyed thereto. A pair of spaced bevel and 34 are rotatably mounted on the and each is provided with clutch teeth 3 respectively, whereby the clutch memb which. is slidably keyed to the shaft 30 may be thrown into engagement with either the clutch teeth or the clutch teeth 36 to rotate either the bevel gear 33 or the bevel gear 34. The bevel gears and 3d mesh with a large bevel gear 31 which is supported on a rotatable shaft 38. The shaft it is provided With a gear 39 which meshes with'a rack bar ii depending from the under side of the table it.

A reversing lever 55 is pivotally mounted on a stud is operatively connected to actuate the slidable clutch member 32. The reversing (:1 11 member 32 may be actuated either manually by means of a pivotally mounted control lever 5i which is connected by means of a rod with. the upper end of the reversing lever 45, or it may be operated automatically by means of table dogs 59 and 58 which are adjustably mounted on the front edge of the table H. By adjustment of the table dogs 49 and 56, the length of the reciprocatory stroke of the work supporting table II may be varied as desired.

The base I6 is provided at its left-hand end (Fig. 1) with an upwardly extending column 55 which has a longitudinally extending aperture through which the end of the table Ii may be passed during reciprocation thereof. The column 55 serves as a support for a rotatable lapping wheel spindle 56 which supports a lapping wheel 51 on its outer end. The rotatable spindle 56 is eccentrically journalled in a rotatably adjustable sleeve 58 by means of a roller bearing 59 at its left-hand end (Fig. 2) and a sleeve bearing 50. The sleeve 58 is provided with an outwardly extending projection GI which is preferably formed integral with the sleeve 58 or rigidly attached thereto. The sleeve BI is provided with a sleeve bearing 82 which supports the lapping wheel spindle 58 at a point adjacent to the lapping wheel 51.

The sleeve 58 is adjustably supported in a rotatable quill or sleeve III which is in turn journalled in bearings II and I2 formed in the up wardly extending column 55 of the base ID. The sleeve or quill Ill may be rotated by means of a variable speed driving mechanism comprising a speed change gear I3 contained within a gear casing I4 on the front of the machine base It. A manually operable control lever I5 which is pivotally mounted. on a stud I6 serves to slide a driving key (not shown) longitudinally so that any one of the gear combinations may be connected to drive a shaft TI. The outer end of the shaft TI is provided with" a stepped driving pulley I8 which is connected by means of a belt 9 with. a stepped driven pulley 8B which is mounted on a rotatable shaft 8I journalled in a bracket 86. The bracket 86 is fixedly mounted on the end of the column 55 of the base II). The driving pulley 80, for convenience in manufacture, as illustrated in Fig. 2, may be made up of two single pulleys. Shifting the belt from one of step pulleys I8 and 80 to the other serves to change the rotary speed of the shaft 8| when desired. The shaft BI is provided with a gear 82 which meshes with a large gear 83 which in turn is mounted on the periphery of the sleeve or quill III. A hand wheel 84 is mounted on the outer end of the shaft 8| to facilitate manual rotation of the sleeve I in setting up the machine.

The wheel spindle 56, which is mounted eccentrically within the sleeve 58, is revolved due to rotation of the sleeve I0 so as to produce a planetary movement of the rotatable lapping wheel 51. It is desirable to provide means for adjusting the eccentricity of the wheel spindle 56 to produce the desired feeding movement of the lapping wheeel as it is rotated and revolved. In the preferred construction, an adjusting mechanism is provided comprising a worm gear 9!! which is mounted on the periphery of the sleeve 58. The worm gear 90 meshes with a worm wheel 9!. By rotation of the Worm 9|, the worm gear 90 is rotatably supported on the end of the sleeve or quill I0 so that a rotary motion of the worm 9| will rotate the sleeve 58 within the quill 'lIl so that the axis of the wheel spindle 56 may be caused to approach or recede from the axis of rotation of the quill I0 to vary the eccentricity of the wheel spindle 56 as desired. The worm 95 may be adjusted manually or, if desired, it may be adjusted automatically by means of a pawl and ratchet mechanism, such as that shown in the expired U. S. patent to Heald No. 888.496 dated May 26, 1908. The details of this mechanism have not been illustrated in the present case since this mechanism is not considered to be a part of the present invention and, being an old and well known feeding mechanism, reference may be had to the above-mentioned patent for details of disclosure not contained herein.

The wheel spindle B is provided with a large driving pulley 95 and a smaller driving pulley 98 by means of which the wheel may be driven at either of two or more speeds. Due to the fact that the wheel spindle revolves during rotation, it is necessary to provide a suitable driving means for the spindle which may comprise a shaft IIIIl which is adjustably supported adjacent to the upper end of the long. arm IilI of a bell crank lever I52 which is pivotally mounted on a stud I83. A spring I04 is connected between a lug I05 formed integral with the column 55 of the base l6 and an adjustable screw I06 which is carried by ashort arm Ill! of the bell crank lever IE2. The tension spring I04 is arranged to produce a thrust of the bell crank lever I02 in a counterclockwise direction (Fig.3). The shaft I00 serves as a rotatable support for a sleeve I III which in turn supports a large diameter pulley III. The pulley III is connected by means of a V-belt II 2 with a pulley I I3 mounted on the end of the main drive shaft I8. This driving arrangement serves to drive the sleeve III) at a relatively slow rate of speed. The main drive shaft I8 is also provided with a large diameter pulley II5 which may be connected by means of a driving belt I I6 with a small diameter pulley I I1 formed integral with the sleeve H8. The sleeve II I] also is provided with a small diameter pulley 96a and a larger diameter pulley II8 either of which may be connected to rotate the wheel spindle 56. The pulley I I8 on the sleeve I I0 may be connected by driving belts I I9 with the small diameter pulley 96 on the spindle 55 to rotate the spindle at a fast speed. 01' the pulley 96a may be connected by driving belts I29 with the larger diameter pulley 95 carried by the spindle 58 to rotate the wheel spindle 56 at a slower rate of speed.

The pulley III is preferably constructed so that it may be readily removed when the wheel spindle 55 and the quill III are rotated at a fast speed to prevent any undue vibration being set,

up within the machine. The pulley I I I is mounted on a frusto-conical surface I2I formed on the sleeve I I I! which mates with a correspondingly shaped aperture within the pulley III. A collar 522 is screw threaded onto the outer end of the sleeve III) and serves to hold the pulley in operating position and also to facilitate the pulley being readily removed when desired.

To produce a highly refined surface on a work piece, it is desirable to impart a relative oscillating or reciprocating movement between the lapping wheel and work piece in addition to its normal reciprocatory or traversing movement. In the present case, a wheel spindle reciprocating movement is provided to reciprocate the lapping wheel spindle 5B axially within its bearings as it rotates and revolves. In the preferred form, an electrically driven reciprocating mechanism is provided in which a variable speed electric motor I30 is mounted on top of a bracket I3I which is fixed by the supporting brackets I32 to the column 55 of the base I0, thus supporting the motor I35 in a fixed relationship with the base ID. The motor drive shaft I33 is connected by means of a coupling I34 with a rotatable shaft I35 which is journalled in adjustably mounted bearings I36 and I37, respectively. A pulley I38 is mounted on the shaft I35. This pulley I38 is preferably a multiple V-grooved pulley, such as is used with a multiple V-belt drive. The pulley I38 is connected by a pair of 'V-belts I39 with a multi grooved pulley I 46 which is supported on a rotatable shaft I M journalled in adjustably mounted bearings I 42 and I43 which are in turn carried by brackets I44 and I45 depending from the under side of the support I3I. The shaft MI is arranged at right angles to the drive shaft I35, consequently an idler pulley I 46 is provided which is' mounted on a supporting stud I4! to facilitate smooth running of the driving belts I39.

A pair of spaced brackets 5% are fixedly mounted to rotate with the pulley Hill. The adjacent edges of the brackets lEil are spaced apart to form an elongated slot 52. A pitman stud or bolt I52 having an enlarged head I53: slides within the elongated slot Iiil and serves as a support for one end of a connecting rod I54. A bushing R55 serves to facilitate free rotation of the stud I52 within the end of the connecting rod I54. A clamping nut I56 is mounted on a threaded end portion I57 of the stud I52 and serves to clamp the stud I52 in adjusted position. If the axis of the stud I52 is adjusted so that it is concentric with. the axis of the shaft hit, then no motion will be transmitted to the connecting rod I54. If a reciprocating movement of the wheel is desired, the stud or crankpin E52 is adjusted so that its axis is eccentric to the axis of the shaft M! by an amount equal to one half the desired reciprocatory stroke of the lapping wheel. The clamping nut 155 is then tightened and a reciprocatory movement will be transmitted to the lapping wheel by a mechanism to be hereinafter described.

Due to the combined rotary and planetary movement of the wheel spindle 56, it is necessary to provide a connection to the wheel spindle whereby it may be reciprocated during the rotary and planetary movement thereof. A disk IE6 is supported by an anti-friction bearing on the end of the wheel spindle or, as illustrated in the drawings, on the end of the sleeve which supports the spindle driving-pulleys 95 and at The disk 5% is free to rotate relative to the spindle 55 and to revolve with it. A cylindrically shaped box-like construction is provided to surround the disk Hi5 and to engage the side faces of the disk Hit! so as to permit a planetary motion thereof and at the same time to permit transmission of an axial reciprocatory movement to the wheel spindle 56. This box-like construction comprises a flanged plate 555 (Fig. 2) which supports an annular ring Hit. The ring M5 in turn supports a cover plate or disk iii'i. The gap between the plate H55 and Ifil sufficient in width either to engage the side faces of the disk it!) in the preferred con" structien, to engage liners iliiia which mounted around the side faces of the disk ifiil. A central aperture 568 within the disk It? permits free planetary movement of the disk itt during rotation and planetary motion of the wheel 5'! and its supporting spindle 5 5.

The plate 5 35 supports a yoke-shaped bracket ill. In order to facilitate supporting the plates I and it! so that they are free to move in a substantially straight-line direction, so as to hold the same with its axis parallel to the axis of the lapping wheel, a pair of pivotally mounted arms H! and I72 are supported. by studs 5'43 and i'l l. respectively, on the supporting frame mi. The lower ends of the arms ill and H2 are yokeshaped (Fig. 5') and arranged to straddle the arms of the yoke-shaped bracket I10 and are pivotally connected thereto by means of studs I15 and I18. The connecting rod E54 rides between the arms of the yoke-shaped bracket I and is connected by means of the stud H6 to transmit an oscillating or reciprocating movement to the plate IE5 and the plate IE1 which in turn transmit a reciprocatory movement to the lapping wheel spindle 58 and the lapping wheel 5'! during its rotary and planetary movement.

'Due to the fact that the disk Itil is free to rotate relative to the spindle 56, there is only very limited movement between the disk Ififi and the plates I65 and I6! since the plate I60 may creep within its confined space due to the planetary movement of the spindle but is not required to rotate with the spindle. Itwill be readily ap parent from the foregoing construction that when the motor I 3% is set in rotation and the stud or crankpin I52 is set oil-center, a reciprocatory movement will be transmitted to cause an axial movement of the wheel spindle 56 within its bearings.

The motor I30 is a variable speed motor by means of which the speed of reciprocation of the grinding wheel may be varied as desired. A rheostat i is mounted on the frame I3I and is connected to control the-speed of the motor 30. By manipulation of the rheostat iBil, the speed of the reciprocatory movement of the lapping wheel 5? may be varied as desired. By varying the eccentricity of the crankpin or stud 152, the length of the reciprocatory stroke of the lapping wheel may be varied as desired.

he operation of this improved machine will be readily apparent from the foregoing. disclosure. Assuming all of the parts to have been previously adjusted. and the speed change mechanisms have been adjusted to the required speeds, a work piece having a hole to be ground to a micro-finish is mounted on the adjustable platen I2 of the table 5! and the platen is adjusted vertically and transversely so that the axis of the hole to be ground is in alignment with the axis of rotation of the sleeve or quill iii. A push button I SE is then actuated to start the main driving motor I5 to cause a reciprocatory movement of the table I i and at the sametime to start the rotation and revolution of the rotary lapping wheel 51. A push button 582 may then be actuated to start the rotation of the wheel spindle reciprocating motor Hill which, through the mechanism above described, s-tarts the reciprocation of the lapping wheel spindle 52 within its sup-porting bearings to cause a comparatively rapid reciprocation of the grinding wheel during its rotary and planetary motions and also during the relative reciprocating or traversing motion between the lapping wheel 5's and the work supporting table Ii. The lapping wheel 57 may then be brought into operative grinding contact with the work piece by manual or automatic actuation of the worm 9i and worm gear to shift the planetary support for the spindle 55 until the wheel is moved into lapping contact with the surface to be generated. As above described, the wheel may be caused to reciprocate through a variable stroke and at a variable speed to produce the desired result. The speed of rotation of the grinding wheel spindle 55 and also of the sleeve or quill 'lli may be at one of several speeds so that the wheel may rotate slowly and revolve rapidly or rotate rapidly and revolve slowly, depending upon the type of work being lapped and also the finish desired. By manipulation of the various driving elements, these speed changes may be made to produce the desired and predetermined results.

As the lapping wheel laps away the internal cylindrical surface of the work piece, the, eccentricity of the wheel spindle 56 may be adjusted manually or automatically to cause the wheel axis to move away from the axis of rotation of the sleeve or quill ll) so as to feed the lapping wheel toward the surface of the work being ground.

It will thus be seen that there has been provided by this invention apparatus in which the various objects hereinabove set forth together with many thoroughly practical advantages are successfully achieved. As many possible embodiments may be made of the above invention and as many changes might be made in the embodiment above set forth, it is to be understood that all matter hereinbefore set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

I claim:

1. In a lapping machine, a work support, a rotatable lapping wheel, means relatively to reciprocate said work support and wheel, spindle bearings, a rotatable Wheel spindle therefor which is axially movable within its bearings, means to rotate and revolve said spindle to impart a rotary and planetary movement to said lapping wheel, and means continuously to reciprocate said spindle axially within its bearings through a comparatively short stroke during the rotation and revolution of said spindle.

2. In a lapping machine, a work support, a rotatable lapping wheel, means relatively to reciprocate said work support and wheel, a 1'0- tatable spindle to support said wheel, a rotatable sleeve to support said spindle, spindle bearings within said sleeve which are arranged eccentric with respect to the axis of rotation of said sleeve, means to rotate said spindle and lapping wheel, means to rotate said sleeve to impart a plentary movement to said spindle and lapping wheel, and means continuously to reciprocate said spindle axially within its bearings through a comparatively short stroke during rotation and revolution thereof.

3. In a lapping machine, a work support, a rotatable lapping wheel, means relatively to reciprocate said work support and wheel, a rotatable spindle to support said wheel, a rotatable sleeve to support said spindle, spindle bearings within said sleeve which are arranged eccentric with respect to the axis of rotation of said sleeve, means to adjust the position of said bearings with respect to the axis of said sleeve to vary the eccentricity thereof, means to rotate said spindle and lapping wheel, means to rotate said sleeve to impart a planetary movement to said spindle and wheel, and a spindle reciprocating mechanism continuously to reciprocate said spindle axially within its bearings through a comparatively short stroke during rotation and revolution thereof.

4. In a lapping machine, a rotatable lapping wheel, bearings therefor, a rotatable wheel spindle therefor which is axially movable within its bearings, means to rotate and revolve said spindle to impart a rotary and planetary movement to said lapping wheel, and a wheel spindle reciprocating mechanism including a freely rotatable disk on said spindle, a movable housing surrounding said disk which is arranged so that the disk is free to move within the housing as the spindle revolves, and means including an adjustable pitman to reciprocate said housing, disk, spindle and wheel.

5. In a lapping machine, a rotatable lapping wheel, a rotatable spindle therefor which is axially movable within its bearings, means to rotate and revolve said spindle to impart a rotary and planetary movement to said lapping wheel, and means including a wheel spindle reciprocating mechanism including a freely rotatable disk on said spindle, a movable housing stu'rounding said disk which is arranged so that the disk is free to move within the housing as the spindle revolves, an adjustable pitman, operative connections between said pitman and said housing to transmit a reciprocatory stroke to said housing and to the grinding wheel, and means including a variable speed motor to drive said pitman.

6. In a lapping machine, a work support, a rotatable lapping wheel, means relatively to reciprocate said work support and wheel, a rotatable spindle to support said wheel, a rotatably adjustable sleeve eccentrically to support said spindle, bearings in said sleeve for said spindle which are arranged to permit an axial reciprocation of the spindle, a second rotatably mounted sleeve which surrounds and supports the first sleeve eccentric relative to the axis of rotation of the second sleeve, means to rotate said spindle and lapping wheel, means to rotate said second sleeve to impart a planetary movement to said wheel during rotation thereof, and means including a variable speed motor to reciprocate said spindle axially relative to its bearings through a relatively short stroke during its rotary and planetary movement.

'7. In a lapping machine, a work support, a rotatable lapping wheel, means relatively to reciprocate said work support and wheel, a rotatable spindle to support said wheel, a rotatably adjustable sleeve, bearings in said sleeve to support the wheel spindle for an axial movement relative thereto with its axis eccentric to the axis of said sleeve, a rotatable sleeve to support said first sleeve eccentric relative to its axis of rotation, means rotatably to adjust the first sleeve relative to the second sleeve to vary the eccentricity of said wheel spindle, means to rotate said wheel at one of a plurality of speeds, means to rotate said second sleeve at one of a plurality of speeds to produce a plentary movement of said wheel during rotation thereof, and means continuously to reciprocate said lapping wheel spindle within its bearings at a variable speed through a relatively short stroke.

8. In a lapping machine, a base, a longitudinally reciprocable work supporting table thereon, means to reciprocate said table through a variable stroke and at variable speeds, a rotatable lapping wheel, means to rotate said wheel at one of a plurality of speeds, an adjustable sleeve surrounding said spindle, eccentrically mounted bearings in said sleeve to support said spindle, a rotatable sleeve eccentrically to support said adjustable sleeve, means to adjust the first sleeve relative to the rotatable sleeve to vary the eccentricity of the wheel spindle relative to the rotatable sleeve, means to rotate said sleeve at one of a plurality of speeds to produce a planetary movement of said wheel during rotation thereof, and means continuously to reciprocate said wheel spindle axially within its bearings at variable speeds.

9. In a lapping machine having a base, a longitudinally reciprocable work supporting table thereon, means including a change speed gear mechanism to reciprocate said table through a variable stroke and at a variable speed, a rotatable lapping wheel, means including a belt'drive to rotate said wheel at one of a plurality of speeds, an adjustable sleeve surrounding said spindle, eccentrically mounted bearings in said sleeve to support said spindle, a rotatable sleeve eccentrically to support said adjustable sleeve, a feeding mechanism to adjust the first sleeve in relative to the rotatable sleeve to vary the eccentricity of the wheel spindle relative to the rotatable sleeve, means including a change speed gear driving mechanism to rotate said sleeve at one of a plurality of speeds to produce a planetary movement of said wheel during rotation thereof, and. means including a variable speed electric motor to reciprocate said spindle axially within its bearings at a variable speed through a relatively short stroke.

HERBERT S. INDGE. 

